1. Field of the Invention
The present invention relates generally to moldable articles and compositions for making the same. In particular, the invention relates to articles that are heat-moldable.
2. Background Art
It is becoming more and more desirable to provide wearers with customized articles for sporting goods and the like. Such articles provide the wearer with a greater degree of comfort and support. One way this customization can be achieved is by producing articles that simulate the contours of a particular part of the body on which they are worn or used. Examples include footbeds that simulate the bottom contours of the human foot, racquet handles that simulate the contours of the hand, helmets that simulate the contours of the head, and shin pieces that simulate the contours of the lower leg.
A number of approaches have been developed to provide customized articles. In one approach, the article includes a layer of thermoplastic material which will soften when heated. The wearer then presses a body part against the heated article, creating an impression. The thermoplastic material is then allowed to cool while retaining the impression of the wearer's body part. An example of this approach is disclosed in U.S. Pat. No. 5,733,647. In this example, the thermoplastic material comprises a mixture of ethylene copolymers and/or ethylene terpolymers with an ethylene terpolymer such as ethylene vinyl acetate modified by the addition of carbonyl groups incorporated as part of the main chain. While the thermoplastic material disclosed in U.S. Pat. No. 5,733,647 can be heated and molded, it is a non-foam material which reduces the comfort provided by the article and microwave heating a thermoplastic material that includes carbonyl groups in the main chain can result in the emission of toxic carbon monoxide fumes. Obviously, this is dangerous for consumers who may choose to mold the article at home.
Thus, the need exists for an article which can be custom molded in a simple and efficient manner, without the possibility of emitting toxic fumes.